How to use dispatch queue for high Priority in background in Swift 3.1

Question

    let dict_one=result[i]

    let product:AllProducts=AllProducts()

    product.applications=dict_one.objectForKey("applications") as? String

    product.desc=dict_one.objectForKey("description") as? String

    product.familyId=String(dict_one.objectForKey("familyId") as! Int)

    if dict_one.objectForKey("imageName") as? String  != nil
    {
        product.imageName=dict_one.objectForKey("imageName") as? String

        let url:String =  AppConstant.GetAllImages + (dict_one.objectForKey("imageName") as? String)!

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0))
        {
         let imagePath=self.fileInDocumentsDirectory((dict_one.objectForKey("imageName") as? String)!)
         self.saveImage(url, image_name1: (dict_one.objectForKey("imageName") as? String)!,path: imagePath)
        }
    }
    else
    {
        product.imageName=""
    }

I need to use dispatch queue for high Priority in background in swift 3.1 can you help to find out the solution?

Answer 1

Here you go:

DispatchQueue.global(qos: .userInitiated).async {
     //Your code goes here

     //Coming back to the main queue to update the UI
     DispatchQueue.main.async {
         //Update your ui (reloading tableView, Label update, etc. here)
     }
}

Hope this helps.